Laundry stacking machine

ABSTRACT

A machine for folding and stacking laundry articles comprising a clamp having a pair of substantially horizontal elongate jaws; tucking means for tucking a laundry article between the jaws to allow the article to be clamped at a fold line; and driving means for swinging the clamp about and over a substantially horizontal axis so that the body of the clamped article is flung outwardly down on to a stack where the article is released from the jaws.

United States Patent Weir [S41 LAUNDRY STACKING MACHINE [72] Inventor:Henry John Weir, 37, Ormerod Road, Chepstow, England [22] Filed: Nov.20, 1970 211 Appl. No.: 91,326

[30] Foreign Application Priority Data Nov. 22, 1969 Great Britain..57,260/69 [52] U.S. Cl. ..270/83 [51] Int. Cl. ..B65h 45/18 [58] Fieldof Search ..270/83, 84, 85, 78

[56] References Cited UNITED STATES PATENTS Seymour ..270/78 [451 Nov.21, 1972 1,048,357 12/1912 Seymour ..270/78X Primary Examiner-Wm. l-l.Grieb AttorneyWenderoth, Lind & Ponack [57] ABSTRACT A machine forfolding and stacking laundry articles comprising a clamp having a pairof substantially horizontal elongate jaws; tucking means for tucking alaundry article between the jaws to allow the article to be clamped at afold line; and driving means for swinging the clamp about and over asubstantially horizontal axis so that the body of the clamped article isflung outwardly down on to a stack where the article is released fromthe jaws.

9 Claims, 7 Drawing Figures PATENTEUunv 21 m2 3. 7 03,280

sum 1 or 3 HENRY JOHN WEIR, Inventor Attorneys PATENTEURH I972 3.703.280

' sum 2 OF 3 HENRY JOHN WEIR, Invntor Attorneys- PATENTEDNHVZI m23.703.280

SHEET 3 BF 3 HENRY JOHN WEIR, Inventor Attorneys LAUNDRY STACKINGMACHINE The invention relates to a machine forfolding and stackinglaundry articles, particularly flat-work articles such as bed-sheets,towels, tablecloths and the like.

At the present time laundry articles, after being ironed in a rotaryironing machine are passed to a folding machine which may effect two,three or four folds. The folded article may be delivered to a stackingmachine which forms them into stacks. An object of the present inventionis to provide a machine which not only performs a stacking function butalso effects the final fold.

According to the invention there is provided a machine for folding andstacking laundry articles comprising a clamp having a pair ofsubstantially horizontal elongate jaws; tucking means for tucking alaundry article between the jaws to allow the article to be clamped at afold line; and driving means for swinging the clamp about and over asubstantially horizontal axis so that the body of the clamped article isflung outwardly down on to a stack where the article is released fromthe jaws.

Preferably the jaws are constituted by a pair of parallel plates andpreferably they are opened and closed by pneumatic cylinders.

In a preferred arrangement the jaws face downwardly at the tuckingposition so that the articles are pushed up into the jaws, whereupon theclamp is swung through about 270 to the stack. This allows the stack tobe higher than the tucking position and this is a convenient feature.However, it is possible for the tucking position to be diametricallyopposite the stacking position, in which case the jaws are directedhorizontally at the tucking position, the laundry articles being tuckedbetween the jaws by a horizontal movement.

Preferably the article is fed to the tucking position on a conveyorwhich runs beneath the jaws, tucking means being actuated in response toone or .more timing switches. The articles may be fed in a directiontransat a fold line perpendicular to the direction of travel. In thiscase a two speed measuring system operated by one or two timing switchesis used to actuate the tucking means at the appropriate time.

Alternatively, the articles may be fed parallel to the length of thejaws so as to be cross-folded, the fold line being fed directly beneaththe jaws. In this case no measuring system is required, the tuckingmeans being actuated directly by a simple sensing switch.

The tucking means may comprise a tucking blade or fingers projectedbetween conveyor bands by a pneumatic actuator, for example, or a seriesof air jets.

The invention will further be described with reference to theaccompanying drawings, of which:

FIG. 1 is an end elevation of a stacking and folding machine inaccordance with the invention;

FIG. 2 is a side elevation of the machine of FIG. 1;

FIG. 3 is an electrical and pneumatic circuit diagram of the machine ofFIGS. 1 and 2;

FIG. 4 is an end elevation of another stacking and folding machine inaccordance with the invention;

FIG. 5 is a diagrammatic side elevation showing an alternative foldingblade arrangement for another folding machine in accordance with theinvention;

. verse to the length of the clamp jaws so as to be folded FIG. 6 is adiagrammatic end elevation showing a folding blade arrangement for across-folding machine in accordance with the invention; and

FIG. 7 is an end elevation of another machine in accordance with theinvention.

Referring to FIGS. 1 and 2 the machine comprises a two-part conveyor a,a, which runs continuously in the direction shown by the arrows. Laundryarticles to be finally folded and stacked are fed onto the conveyor froma folding machine (not shown) which makes preliminary folds. Thearticles are conveyed beneath a clamp b which has a pair of elongateplate-like clamp jaws c. The clamp b is rotatable about a horizontalaxis d but its normal, rest, position is shown in FIG. I wherein thejaws c are directed vertically downwardly.

A tucking blade e is positioned between the two parts of the conveyorand immediately beneath the rest position of jaws c. The blade iscapable of being pushed upwardly by a pneumatic ram 3. In operation, alaundry article is fed along the conveyor and the passage of the leadingand trailing edges is sensed by two switches S1 and S2 which energize atwo-speed timer device EMC of a kind well known. The timer device iseffective to actuate the air ram 3 so as to tuck the article at apredetermined fold line between the jaws c. The timing device may bearranged so that the fold line is at any required position along thearticle. Customarily the fold line is half-way along the article.

The jaws c are clamped onto the article by a pair of pneumatic cylindersl, the blade e is withdrawn and the clamp b is swung throughapproximately 270 about the axis d in the direction shown by the arrow.The driving means for swinging the clamp comprises a pair of pneumaticrams 2a, 2b, the pistons of which are linked by a chain and sprocketdrive to the shaft at the axis d. The described swinging action flingsthe body of the article outwardly by centrifugal force and lays it flaton the top of a stack of previously folded articles on a table f. Atthis time the jaws c are opened and the clamp b is returned to itsstarting position by the driving rams 2a, 2b. The machine is then readyto fold and stack the next article.

The electric and pneumatic circuits necessary for performing the abovedescribed functions are shown in FIG. 3. In FIG. 3 all the switches andvalves are shown in their normal, or released positions which they adoptwhen the machine is ready to receive an article. The switch contactsclosed by the timing device are shown at EMC in FIG. 3 and closure ofthese contacts supplies a 24 volt potential from line L through a switchS3 to energize an air valve SV2, which supplies air to the 7 lower partof cylinder 3 to raise the tucking blade e. A

microswitch S5 (FIGS. 2 and 3) is engaged by the tucking blade e when atits lowermost position. As soon as the blade is raised switch S5 isopened. When the blade reaches its uppermost position and the fold lineof the article carried thereby is between the jaws c then a microswitchS4 is engaged by the blade and is operated. This applies the voltagefrom line L to energize a relay RLl. The line voltage is also appliedfrom relay RLl to contacts of another relay RL2 which are closed andthence to energize an air valve SVl. Air is thus supplied through partSVlB to the two cylinders l which close the jaws c on the article. Also,one side of ram 2a is connected to atmosphere (exhaust). Another part SV1A of valve SVl supplies air under pressure to the top side of cylinder3.

The closure of the jaws c operates another microswitch S3 mounted on thejaws and this supplies the line voltage to the contact of relay RLl andthus holds this relay on. At the same time, the supply current to valveSV2 is broken and the valve exhausts the lower part of cylinder 3 andallows the piston to be driven downwardly and thus retract the blade e.Switch S4 thus reverts to the condition shown in the drawing. When theblade e reaches the lower position switch S5 again reverts to thecondition shown in the drawing and line voltage is applied throughswitch S5 and a switch S6 to the right hand contact of relay RL2. Athird solenoid valve 8V3 is thereby energized this supplies air underpressure to one side of ram 2b. Both rams 2a, 219 have air underpressure supplied continuously to their upper parts (in FIG. 3) so thatin this condition ram 2b is balanced and exerts no net force on thepiston. However, until that time there was a downward force on thepiston of ram 2b and this was balanced by an equal downward force on thepiston of ram 2a. Thus the effect of balancing the ram 2b byenergization of SV3 produces a net force which rotates the clamp b.Application of air under pressure from valve SV3 also has the effect ofoperating a diaphragm actuator 4 which opens a switch S7.

A earn 5 is mounted on one end of the shaft on which the clamp turns.This cam operates a microswitch S6 and is so arranged that switch S6 isoperated when the clamp 19 is at top dead center. Switch S6 remainsoperated until the clamp returns past top dead center on its returnstroke. Operation of switch S6 de-energizes solenoid 8V3, thus againequalizing the forces exerted by the two rams 2a, 2b. The clamp b istherefore allowed to complete its forward stroke by the effects ofinertia and gravity. The diaphram actuator 4 responds to the fall inpressure in line Pl but this response is such that there is a delay ofabout A see. between de-energization of SV3 and the reversion of switchS7 to its normal position. This time is sufficient to allow the jaws cto fall onto the stack of articles. When switch S7 is released relay RLZis energized through switches S5, S6 and S7. This releases solenoid SV]so that cylinders I are energized to open the jaws c. Through valve SVIBair under pressure is applied on line P to ram 2a. This upsets thebalance in rams 2a, 2b and the clamp b is driven back to its startposition and the machine is ready for the next article.

During the stacking cycle a voltage pulse is applied to a line 6 whichsupplies a pulse counter effective to count the number of articles laidon the stack and, after a predetermined count, say 10 articles, an alarmis initiated so that the stack can be removed either automatically ormanually.

Referring now to FIG. 4 there is shown a machine similar to that ofFIGS. 1 to 3 but with some modifications. Firstly, instead of being adivided conveyor, the conveyor a feeds on to a flat table 16, the jaws cbeing situated above the junction of the conveyor and the table. Thetiming switches 51, S2 (FIG. 1) are provided but are not shown in FIG.4.

Secondly, instead of a tucking blade e there is provided an air tube 7which has a series of air outlet jets spaced along its upper generator.The tube 7 extends for the length of the jaws c and is pressurizedmomentarily with high pressure air when the fold line of the article isabove it. This inserts the fold line between the aws. I

The third difference of the machine of FIG. 4 is that instead of a tablef there is provided a stacking conveyor g which is normally stationarybut which is stepped forward intermittently when the above mentionedpulse counter gives a driving signal indicating that the stack iscomplete.

FIG. 5 illustrates an alternative kind of tucking blade for use when theconveyor a is continuous and is constituted by spaced parallel bands.The blade e has fingers which can project up between the bands to insertthe article between the jaws.

FIG. 6 shows a folding blade arrangement for a crossfolding machine inaccordance with the invention. Here the articles are fed beneath jaws con a conveyor running in a direction parallel to the length of the jaws.The articles are fed so that the required fold line is directly beneathjaws c and when a simple contact switch (not shown) is engaged by thearticle when it is entirely beneath the jaws the fold blade cylinder 3is actuated.

FIG. 7 shows a machine with an alternative method of feeding thearticles. The normal, rest, position for the clamp b is, as shown infull line, with the jaws c directed horizontally away from the stackingtable f. Laundry articles are fed to drape over the end of a conveyor aand the tucking blade e is immediately beneath the conveyor. Theoperating sequence is basically the same as that of the machine ofFlGS.1 to 3, except that the clamp 12 has to move through only about180.

The invention is not restricted to the details of the embodimentsdescribed above with reference to the drawings. For example, two similarmachines may be arranged in series to stack respectively articles ofdifferent sizes, the first machine being bypassed when necessary simplyby de-actuation to allow an article to pass to the second machine.Although the control system described is electro-pneumatic it is to beunderstood that alternative systems may be used which may be entirelyelectrical using solenoid clamps and motor drive for the swingingmovement; or entirely pneumatic-using fluidic switches; or hydraulic; orany combination.

I claim 1. A machine for folding and stacking laundry articles,comprising a clamp having a pair of normally spaced opposed horizontalelongate jaws and means for Y clamping said jaws together and releasingthem, a support'means on which said jaws are rotatably mounted forrotation around a horizontal axis toward a stacking position generalIyto one side of the axis from a tucking position at least about half-wayaround the axis from the stacking position, tucking means adjaeentsaidtucking position for tucking a laundry article between the jaws to allowthe article to be clamped at a fold line, and driving means for drivingthe clamp around and over the horizontal axis in an arcuate path fromthe tucking position to the stacking position at a speed sufficient tocause the body of the article clamped in the jaws to be flung outwardlyas the clamp is swung over the horizontal axis and down onto a stack atthe stacking position, the machine having a clearance along the arcuatepath sufficient to permit the article to extend freely outwardly of theclamp during driving of the clamp along the arcuate path.

2. A machine as claimed in claim 1 wherein the tucking position isbeneath the horizontal axis about three quarters of the way around theaxis from the stacking position and the jaws are downwardly facing atthe tucking position.

3. A machine as claimed in claim 2 further comprising conveyor meansrunning beneath said clamp for feeding the laundry articles to thetucking position, and at least one timing switch along said conveyor andactuated by the laundry article on the conveyor and means responsive tothe timing switch coupled thereto to actuate the tucking means to insertthe article upwardly between the clamp jaws along the fold line. A

4. A machine as claimed in claim 3 wherein the conveyor runstransversely to the length of the jaws and said means responsive to saidtiming switch is a twospeed timing device to actuate the tucking meansat the appropriate time.

5. A machine as claimed in claim 3 wherein the conveyor comprises a setof parallel spaced conveyor bands running parallel to the jaws and thetucking means extends between the conveyor bands, the articles beingpositioned on the conveyor so that the required fold line runs beneaththe jaws.

6. A machine as claimed in claim 1 wherein the tucking position isbehind the horizontal axis about one-half of the way around the axisfrom the stacking position and the jaws are sidewardly facing at thetucking position.

7. A machine as claimed in claim 1 wherein said means for clamping thejaws together and releasing them are pneumatic cylinders.

8. A machine as claimed in claim 1 wherein the driving means comprisesan air ram means having one or more pistons coupled to the clamp forswinging the clamp.

9. A machine as claimed in claim 8 wherein the air ram means is doubleacting for driving the clamp forwards to the stacking position andbackwards to return the clamp to the tucking position.

1. A machine for folding and stacking laundry articles, comprising aclamp having a pair of normally spaced opposed horizontal elongate jawsand means for clamping said jaws together and releasing them, a supportmeans on which said jaws are rotatably mounted for rotation around ahorizontal axis toward a stacking position generally to one side of theaxis from a tucking position at least about half-way around the axisfrom the stacking position, tucking means adjacent said tucking positionfor tucking a laundry article between the jaws to allow the article tobe clamped at a fold line, and driving means for driving the clamparound and over the horizontal axis in an arcuate path from the tuckingposition to the stacking position at a speed sufficient to cause thebody of the article clamped in the jaws to be flung outwardly as theclamp is swung over the horizontal axis and down onto a stack at thestacking position, the machine having a clearance along the arcuate pathsufficient to permit the article to extend freely outwardly of the clampduring driving of the clamp along the arcuate path.
 1. A machine forfolding and stacking laundry articles, comprising a clamp having a pairof normally spaced opposed horizontal elongate jaws and means forclamping said jaws together and releasing them, a support means on whichsaid jaws are rotatably mounted for rotation around a horizontal axistoward a stacking position generally to one side of the axis from atucking position at least about half-way around the axis from thestacking position, tucking means adjacent said tucking position fortucking a laundry article between the jaws to allow the article to beclamped at a fold line, and driving means for driving the clamp aroundand over the horizontal axis in an arcuate path from the tuckingposition to the stacking position at a speed sufficient to cause thebody of the article clamped in the jaws to be flung outwardly as theclamp is swung over the horizontal axis and down onto a stack at thestacking position, the machine having a clearance along the arcuate pathsufficient to permit the article to extend freely outwardly of the clampduring driving of the clamp along the arcuate path.
 2. A machine asclaimed in claim 1 wherein the tucking position is beneath thehorizontal axis about three quarters of the way around the axis from thestacking position and the jaws are downwardly facing at the tuckingposition.
 3. A machine as claimed in claim 2 further comprising conveyormeans running beneath said clamp for feeding the laundry articles to thetucking position, and at least one timing switch along said conveyor andactuated by the laundry article on the conveyor and means responsive tothe timing switch coupled thereto to actuate the tucking means to insertthe article upwardly between the clamp jaws along the fold line.
 4. Amachine as claimed in claim 3 wherein the conveyor runs transversely tothe length of the jaws and said means responsive to said timing switchis a two-speed timing device to actuate the tucking means at theappropriate time.
 5. A machine as claimed in claim 3 wherein theconveyor comprises a set of parallel spaced conveyor bands runningparallel to the jaws and the tucking means extends between the conveyorbands, the articles being positioned on the conveyor so that therequired fold line runs bEneath the jaws.
 6. A machine as claimed inclaim 1 wherein the tucking position is behind the horizontal axis aboutone-half of the way around the axis from the stacking position and thejaws are sidewardly facing at the tucking position.
 7. A machine asclaimed in claim 1 wherein said means for clamping the jaws together andreleasing them are pneumatic cylinders.
 8. A machine as claimed in claim1 wherein the driving means comprises an air ram means having one ormore pistons coupled to the clamp for swinging the clamp.